Propagation of Leaky Surface Waves in Thermoelastic Solids Due to Inviscid Fluid Loadings

Abstract

This article is aimed at studying the propagation of surface waves in a homogeneous, isotropic, thermally conducting elastic solid bordered with layers or half spaces of inviscid liquid in the context of generalized theories of thermoelasticity. After developing formal solutions, secular equations for the solid in closed form and isolated mathematical conditions for leaky Rayleigh waves, leaky Lamb waves, and nonleaky Lamb waves in completely separate terms are derived. The thin-plate wave results for leaky Lamb waves have also been derived. The amplitude ratios of displacement in liquid layers and half spaces are also obtained and computed analytically. The results have been deduced and compared with the relevant publications available in the literature at the appropriate stages of the work. Finally, the numerical solution is carried out for an aluminum-epoxy composite material solid (half space) or plate bordered with water layers of finite and infinite thickness. The dispersion curves, attenuation profiles, and amplitude ratio of displacement in liquid layers and half spaces for symmetric and antisymmetric thermoelastic leaky Lamb waves, leaky Rayleigh waves, and nonleaky Lamb waves are presented and illustrated graphically in order to illustrate and compare the theoretical results. The theory and numerical computations are found to be in close agreement.The study of the interaction of elastic waves with fluid-loaded solids has been recognized as a viable means for nondestructive evaluation of solid structures. The reflected acoustic field from a fluid-solid interface has a wealth of information, which, if exploited, reveals details of many characteristics of solid. These include its properties, the possible existence of internal defects, and also the quality of interface, to name a few. Specifically, the reflected field of a finite-width incident acoustic beam shows unusual behavior in that it is nonspecular, it displaces (shifts) along the interface, and it contains a trailing edge that attenuates away from the center of reflection. This behavior is widely known as the leaky wave phenomenon. These

Thermoelastic waves in coated homogeneous anisotropic materials

“…The corresponding analysis agrees with Sharma and Pathania [20] for Rayleigh waves (leaky and non-leaky) in this case. The results in the context of classical (parabolic) CT and UCT can be obtained by setting t 1 ¼ 0 ¼ t 0 and e ¼ 0, respectively, in the above analysis.…”

“…Achenbach [19] studied the ultrasonic thermoelastic surface wave generation due to focused-beam laser irradiation by presenting a simplified approach. Recently, Sharma and Pathania [20] studied the propagation of leaky surface waves in thermoelastic solids due to inviscid fluid loading.…”

Elasto-Thermodiffusive Surface Waves in a Semiconductor Half-Space Underlying a Fluid with Varying Temperature

“…The exponent in the plane wave solution (11) becomes iR x − Vt − Qx, which shows that V is the propagation speed and Q the attenuation coefficient of the waves. Upon using Equation (21) in secular Equations (17) and (20) along with other relevant relations, the values of phase speed V and attenuation coefficient Q for the propagation of non-leaky and leaky Rayleigh waves can be obtained for different values of the wave number R .…”

“…Upon using solutions (11) in Equations (6), after lengthy but straightforward algebraic reductions and simplifications, we obtain the following formal solution for N T L L that satisfies the radiation conditions R e m i ≥ 0 and Re i ≤ 0 i = 1 2 3 4, we have…”

“…Sharma and Pathania [11,12] studied the propagation characteristics of leaky and non-leaky Rayleigh and plate waves in thermoelastic solids due to inviscid fluid loadings maintained at uniform temperature. Recently, Sharma et al [13] investigated the propagation of generalized Rayleigh surface waves in a homogenous, isotropic, microstretch thermoelastic solid half-space underlying an inviscid liquid half-space (or layer of finite thickness) in the context of classical and "non-classical" theories of thermoelasticity.…”